The present invention relates in general to laser technology for etching of surfaces on a luminaire reflector and more particularly, to an apparatus and method for ablating a surface on a powder coated luminaire reflector with a laser.
Luminaires must be appropriately marked with requisite indicia as set forth in Underwriters Laboratory requirements, particularly in UL 1598 Standard, Second Edition, Section 20. Per the UL requirements, the luminaire must be legibly marked with various information such as is set forth in Section 20.1.1. Historically, luminaire manufacturers have met this requirement by placing a sticker on the interior surface of a luminaire such that when the luminaire is relamped, all of the requisite marking information is legible.
However, problems arise when applying the adhesive backed label or sticker to the interior surface of the luminaire. The interior reflector of a luminaire is made to be as reflective as possible per the requirements of the luminaire specifications. The luminaire typically is designed such that the reflector has necessary reflective characteristics to provide adequate dispersion of light. By placing the sticker with the requisite UL material on the interior reflective surface of the luminaire reflector, the reflective characteristics of the luminaire are negatively modified.
Additional problems arise when applying an adhesive backed sticker to the luminaire reflector. This includes applying the sticker to a curved surface since recessed luminaires typically are frusto-conical in design and curve from the exit aperture upward towards the lamp socket, or along at least a portion thereof. The sticker that is applied must conform to this curved surface. Since the sticker itself is flat and planer, application of the sticker to the curved surface of the interior reflector of the luminaire causes air bubble entrapment within the sticker gathering along the shorter edge, and proper placement is difficult during the manufacturing process.
A further issue is the material on which the sticker is placed. Typical reflectors for recessed luminares are made from hydroformed aluminum or other metal which are then powder coated to provide the smooth white glossy finish which is standard for the reflector in the luminaire industry. This powder coated finish provides an ideal smooth and reflective surface for the luminaire reflector.
Thus, it is desirable to provide a marking method and apparatus for a surface of the luminaire reflector to be marked permanently so as to meet the requirements of UL while also minimum changing the reflective characteristics of the reflector housed within the luminaire.